信息与利用课程双语教学可行性分析

开设信息与利用课程双语教学有利于培养学生的信息素养。保证该课程双语教学的顺利开展,要制订切实可行的规划,建立和完善一系列的保障措施和激励机制。     

我国信息可视化检索研究

在信息可视化基本技术、面向特定信息类型的可视化技术以及大型信息资源可视化技术的基础上,分析了国内近几年信息检索可视化研究的理论探讨、技术开发及实际应用等几个方面。信息检索可视化发展面临没有形成系统的结构、没有将现有的可视化技术综合以及全文可视化等问题。     

基于平行因子分解的大规模MIMO盲信道估计

针对单小区大规模多输入多输出（Multiple-Input Multiple-Output,MIMO）系统上行链路,提出了一种基于平行因子（Parallel Factor,PARAFAC）模型的信道估计方法。在基站端,将接收信号构造成PARAFAC模型,利用大规模MIMO系统中信道的渐近正交的性质,提出了一种基于约束二线性迭代最小二乘算法(Constrained Blinear Alternating Least Squares,CBALS),从而实现了盲信道估计。理论分析及仿真结果表明,所提方法与传统最小二乘方法相比,不仅提高了频带利用率而且具有更高的估计精度;与已有的二线性交替最小二乘方法(BALS)相比,所提算法有更快的收敛速度。     

基于分形编码的图像检索技术

分形编码在图像压缩方面取得了很好的效果,同时,分形编码也能够用于基于内容的图像检索。为了使人们对基于分形编码的图像检索技术有一概括了解,本文对目前分形编码检索技术进行了回顾和讨论:首先,简要介绍了分形编码技术;然后,对现有的分形编码检索技术的发展进行评述,最后,对分形编码检索技术的研究发展及其应用前景指出了一些可能的方向。     

Design implications for task-specific search utilities for retrieval and re-engineering of code

The importance of information retrieval systems is unquestionable in the modern society and both individuals as well as enterprises recognise the benefits of being able to find information effectively. Current code-focused information retrieval systems such as Google Code Search, Codeplex or Koders produce results based on specific keywords. However, these systems do not take into account developers’ context such as development language, technology framework, goal of the project, project complexity and developer’s domain expertise. They also impose additional cognitive burden on users in switching between different interfaces and clicking through to find the relevant code. Hence, they are not used by software developers. In this paper, we discuss how software engineers interact with information and general-purpose information retrieval systems (e.g. Google, Yahoo!) and investigate to what extent domain-specific search and recommendation utilities can be developed in order to support their work-related activities. In order to investigate this, we conducted a user study and found that software engineers followed many identifiable and repeatable work tasks and behaviours. These behaviours can be used to develop implicit relevance feedback-based systems based on the observed retention actions. Moreover, we discuss the implications for the development of task-specific search and collaborative recommendation utilities embedded with the Google standard search engine and Microsoft IntelliSense for retrieval and re-engineering of code. Based on implicit relevance feedback, we have implemented a prototype of the proposed collaborative recommendation system, which was evaluated in a controlled environment simulating the real-world situation of professional software engineers. The evaluation has achieved promising initial results on the precision and recall performance of the system.     

浅析汉语问答系统中的句子检索方法

自动问答系统是自然语言理解研究领域中的热门方向,它综合运用了多种自然语言处理技术。本文首先简单介绍了问答系统中的几种关键技术,然后对问答系统中信息检索模块句子检索的方法和特点进行了分析。     

Systematic acceleration of radical discovery and innovation in science and technology

A systematic two-component approach (front-end component, back-end component) to bridging unconnected disciplines and accelerating potentially radical discovery and innovation (based wholly or partially on text mining procedures) is presented. The front-end component has similar objectives to those in the classical literature-based discovery (LBD) approach, although it is different mechanistically and operationally. The front-end component will systematically identify technical disciplines (and their associated leading experts) that are directly or indirectly-related to solving technical problems of high interest. The back-end component is actually a family of back-end techniques, only one of which shares the strictly literature-based analysis of the classical LBD approach. The non-LBD back-end techniques (literature-assisted discovery) make use of the human experts associated with the disparate literatures (disciplines) uncovered in the front-end to generate radical discovery and innovation.Specifically, in the literature-assisted discovery operational mode, these disparate discipline experts could be used as:

1. Recipients of solicitation announcements (BAA, SBIR, MURI, journal Special Issue calls for papers, etc.),

2. Participants in Workshops, Advisory Panels, Review Panels, Roadmaps, and War Games,

3. Points of Contact for Field Science Advisors, Foreign Field Offices, Program Officer site visits, and potential transitions.

航空人为因素国内期刊文献梳理

人为因素已经成为影响航空安全的重要因素。论文简要介绍了航空安全领域人为因素相关知识;检索了中国期刊全文数据库、万方数据知识服务平台和中文军事科技知识资源总库等三个军内外文献资源平台中收录的航空人为因素与安全的相关期刊文献,对航空人为因素研究进展进行了综述与分析评述。在此基础上,预测了未来国内的航空人为因素研究趋势,建议了研究的侧重点。     

Appropriability and the retrieval of knowledge after spillovers

Research summary: Firms create and capture value through innovation. In technology‐driven firms, there has been an explicit emphasis on appropriability through imitation deterrence and cumulative inventions that build on prior firm innovation. We introduce systematic empirical evidence for a third mechanism of appropriability namely, knowledge retrieval, which is defined as the re‐absorption of previously spilled knowledge. We extend previous studies which consider technological complexity and organizational coupling as predictors of appropriability by examining their impact on knowledge retrieval. We find that technological complexity has a curvilinear relationship with retrieval while organizational coupling has a negative relationship. We discuss the implications of these findings for theories of absorptive capacity, organizational design and appropriability of innovation. Managerial summary: It is a widely held assumption that knowledge should be protected and held tightly within the firm to ensure value creation and value capture. The implicit recognition is that knowledge spillovers, or knowledge leakage, is detrimental to performance. By examining the patterns of citations among patents of 142 semiconductor firms, we study how organizational structure and technological complexity play a role. We find that moderate technological complexity improves appropriability. If imitation deterrence is paramount, then the optimal structure would be a tightly‐coupled organization. In other instances, loosely‐coupled organizations may be superior because they foster internal cumulative innovations and, if spillovers were to occur, they also maximize knowledge retrieval. Our findings suggest that all is not lost when spillovers occur and that firms can continue to benefit in downstream innovations. Copyright © 2015 John Wiley & Sons, Ltd.     

三频段准连续波雷达信号目标检测性能分析

准连续波雷达是一种低截获概率雷达,结合了脉冲雷达收发隔离和连续波雷达截获概率低的优点,但其检测性能的优劣很大程度依赖于信号形式,普通的编码信号和线性调频信号已经不能满足其对目标探测的要求。为解决这个问题,设计了一种三频段信号和与之相应的收发系统,对系统结构及三频段信号的参数选择原则、目标检测原理、模糊函数、抗近距离盲区性能做了详细分析,并指出了三频段信号相对于相位编码信号和分时发射信号的优势所在,最后通过仿真证明,将三频段信号应用于准连续波体制雷达中时能准确探测目标,得到目标的各个参数并且能有效消除近距离盲区。